I now understand this 'dependency Hell' thing of which people occasionally speak. I have been there.
The package I wanted on my laptop wasn't in Debian Etch (Stable). I tried a site full of backports but although they had the package, they hadn't put it in their lists, so I couldn't resolve the dependencies. I tried to build it from source, but again got stuck somewhere along a huge chain of building dependencies. In the end, I decided to risk all and upgrade the distribution.

I'm now running Debian Sid (Unstable). After all, what's the worst that could happen?